Metal is a physically durable material, but when it’s being shipped over long distances, it needs to be protected against more than just knocks and bumps. The nature of international shipping means that the risks of moisture damage like rust and corrosion are higher, so it’s important to take proactive steps against them.
The right type of packaging plays a decisive role. In most cases, standard packaging won’t be sufficient for export packing on its own, but there are several specialist additions that can help to make it a viable option; including barrier foils, VCI packaging and desiccants. If corrosion and moisture damage is an issue that you’re currently dealing with when it comes to your own shipments, you can always rely on our team to help.
To get you started, here’s a quick guide on the key information you’ll need to know about the various different types of protective materials, so you can start making informed decisions on which one is best suited to your shipment.
Why is metal equipment vulnerable during transit?
Metal equipment and components tend to be vulnerable in transit mainly because of the specific conditions that are characteristic of freight travel by sea or air. Bumps, collisions and other sudden shocks are obviously a universal concern for all types of cargo. In addition to these though, a big part of the reason why moisture damage is such a major concern for metal cargo is because there’s a variety of ways in which it can occur, affecting internal components and external surfaces.
The main threats include:
- Rust due to condensation that often forms during temperature fluctuations during sea freight
- Higher risk of corrosion upon arrival at tropical or humid destination climates
- Sustained humidity during long transit times (potentially weeks or months), creating further conditions for rust or corrosion
- Surface damage due to metal-on-metal contact during vibration or movement
- No vapour barrier in standard cardboard or wooden casing, allowing moisture and humidity to move freely within the packaging
Any of these can result in equipment that has to be repaired or even replaced once it reaches its destination, which can have wider consequences for your business. For example, it can result in extra costs, expensive delays and disruptions, and potentially unhappy customers.
Barrier foils, VCI packaging and desiccants have all been designed to protect metal shipments against exactly these sorts of risks, which is why we offer each of them as an additional option for your cargo here at Tuplin, and can recommend them according to the requirements of your items.
What is a barrier foil?
A barrier foil is a laminated foil that’s designed to create a hermetically-sealed, moisture proof envelope around an item. In doing so, it protects it from external contaminants like moisture, oxygen, UV light and chemicals.
At a glance:
- Provides a sealed, moisture-resistant enclosure that can protect your goods from humidity and moisture damage
- Can be heat-sealed around your goods to maintain a stable internal environment throughout handling and transport
- Commonly used for machinery, electronics, and high-value equipment that needs protection during storage and export
In more detail:
It’s a high-performance composite material typically made from layers of polyester, aluminium foil and polyethylene. It protects metal components from moisture damage by basically eliminating the conditions in which corrosion can occur. During packing, each piece of equipment is enclosed within a foil barrier and heat sealed to form an airtight layer. This restricts the movement of moisture and water vapour, protecting the component throughout transit and storage.
It’s frequently used in combination with desiccants – the heat-sealing part of the process occurs after the desiccants are placed inside. These draw in the moisture from the air, helping to create a closed environment that makes it virtually impossible for rust or condensation to form.
Barrier foil in export packing is most commonly used for equipment being shipped to environments with high humidity, or extended trips overseas, or being put into long-term storage – all of which pose a relatively high risk of moisture damage. It’s a go-to option for particularly sensitive parts such as precision instruments, aerospace components, CNC machinery and electronic equipment, all of which are especially vulnerable to rust and condensation.
A quick overview of VCI packaging
VCI stands for Volatile Corrosion Inhibitor. It’s anti-corrosion packaging, specifically designed to prevent metal parts and components from corroding when they’re being stored or transported.
At a glance:
- VCI packaging releases corrosion-inhibiting compounds that form a protective molecular layer on metal surfaces
- It can protect ferrous and non-ferrous metals from rust and oxidation during storage and transit
- It allows your goods to be unpacked and used immediately without additional cleaning or treatment
In more detail:
The packaging contains VCIs, which are corrosion-inhibiting compounds that actively release anti-corrosion molecules. VCI packaging for metal equipment is available in film, paper, foam and emitter formats. These materials are used to create an enclosed space (not necessarily an airtight one) around the item. Within this space, the compounds actively release anti-corrosion molecules, which form a microscopic layer on top of the metal. This blocks the electrochemical process that creates rust.
It’s worth noting that it’s an extremely thin coating, and doesn’t affect the performance of the metal. The inhibitor dissipates harmlessly and doesn’t leave any residue behind, so the equipment doesn’t require any cleaning at its destination before it’s put into service. It’s particularly effective for complex machined parts, ferrous and non-ferrous metals, as well as anything that can’t be fully sealed in barrier foil.
What is a desiccant, and how are they used in packing and export?
Desiccant is the collective name for hygroscopic materials that remove surrounding humidity by absorbing moisture from the air.
At a glance:
- Absorbs moisture within enclosed packaging to control internal humidity levels
- It can prevent condensation from forming around your goods during transit and storage
- Available in different capacities to match the volume and sensitivity of your shipment
In more detail:
In packaging and export, desiccants are placed inside sealed packaging to maintain a low-humidity environment. There are several different types – the most common is silica gel, but some of the more popular alternatives include the naturally-derived desiccant clay and synthetic molecular sieve, which are each suited to different temperature ranges. (Desiccant clay is popular with companies looking for a more eco-friendly option, due to the lack of plastic in its chemical makeup.) As we touched on above, desiccant materials are often used with heat-sealed barrier foil, as they remove any residual moisture trapped inside the seal at the point of packing.
The amount required for each individual shipment is influenced by a range of different factors, including the volume of the sealed space, the duration of time that the cargo is expected to be in transit for, and the humidity levels within it. When it comes to desiccant packing for shipping, it’s important to judge the amount correctly – too few desiccants can reach saturation point too early (capping the amount of moisture they absorb) whereas too many can result in unnecessary extra costs for no tangible corresponding benefit.
How we combine these materials in an export pack at Tuplin
At Tuplin, we take pride in providing a complete end-to-end service that encompasses every aspect of the packing and export process. With each shipment, our team will assess the key characteristics of the item itself (including any special requirements related to its packing or handling), as well as its final destination, the mode of transport, and time it will be in transit. We’ll use this information as a basis to decide what materials are best suited towards giving your goods the best protection.
If you have any high value or precision metal equipment for example, our typical pack may include a custom timber or plywood case, a shock-absorbing foam lining, VCI film wrap, heat-sealed barrier foil, and calibrated desiccant sachets.
We hold a wide range of protective materials in stock at all four of our sites, including those located next to major airports like Gatwick and Stansted, so we can always guarantee fast turnaround.
Choose our team at Tuplin for complete peace of mind
Over more than 40 years in operation at Tuplin, we’re proud to have become the first choice for engineers, technical project managers, export co-ordinators and logistics teams all over the UK. Whether you’re shipping precision components, machinery or instruments internationally, you can always rely on us to have the export packing expertise, equipment and connections in-house to ensure the integrity of your cargo throughout its journey.
Contact us today to discuss your project – and if you have any specific requirements for your goods, we’ll be happy to discuss these with you, or else we can advise you as necessary.
